【正确答案】 C

【答案解析】解析：本题容易误选B，认为we worked是强调句式that后面的内容。事实上这是一个省略了that后面内容的强调句，根据问句可知，完整回答应是It is in the factory where we worked that I got to know him．因此空格后的we worked是定语从句，需用连接副词where。